digital zoom. 

You need to use a Retractable Rubber Hood with an internal and external screw thread. You mount the hood first, then you screw the filter to the hood. You retract the hood then you turn the filter to desired ND adjustment. I can reach and turn it without retracting the hood. 

For camera with telephoto zoom lens, you need to buy a tripod mount ring additionally or telephoto lens bracket for better balance) 

The adapter will mount the lens and you will be able to use it manually. However, my copy of the adapter does not allow the lens to be fully mounted all the way until it clicks into place. It doesn't quite make it, but it's still very solidly mounted. Also, the manual aperture linkage doesn't work properly (on my copy, at least) so exposure is controlled only by shutter speed and/or ISO. You will be able to manually focus and zoom the lens but no VR, of course. It will be a frustrating experience. Instead, get a 14-140 Panasonic zoom if you can afford it! 

Yes, 4x zoom.